[Interhemispheric integration and role of the midbrain in its achievement]

In addition to two previously discovered midbrain systems of connections between forebrain hemispheres, surgical, electrophysiological and conditioned analysis revealed in cats another system of midbrain connections mediating interhemispheric interrelations. It represents functional projections of the anterior colliculus to the contralateral posterothalamic nuclear complex via the reticular formation or/and via the reticular formation and the contralateral anterior colliculus. By its structural organization this system occupies an intermediate position as compared to the described two systems because it involves the same structures. It seems to participate in conducting efferent (executive) or coordinating influences.